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land area) at the beginning of June to 1.3 million acres

(55% of total land area) in July.

 Figure 58 gives the water model with input and

simulated total annual values as they might have been for

the same year (1974-75) under primitive (predrainage)

conditions. Simulated total annual runoff was

approximately 13% of total annual rainfall and simulated

total annual ET was 80% of rainfall. The year ended in May

with 7% of rainfall added to storage. During the year soil

water varied from a low of 2 million acre ft at the

beginning of June to a maximum of 3.8 million acre ft (same

as under "present" conditions) in August. Surface water

volume varied from a minimum of 0.46 million acre ft at the

beginning of June to a maximum of 3.7 million acre ft in

August. Land area covered by surface water varied from a

minimum of 0.46 million acres (19% of total land area) at

the beginning of June to a maximum of 2 million acres (83%

of total land area) in August.

Constants

 Given in Appendix Tables C-I through C-5 are the

constants used as coefficients and thresholds in equations

for the water model in Figure 14 of Methods (see also

Equation 9 through 15). Table C-i shows values used in the

equation for interflow. Table C-2 shows values used in the

equation for groundwater flow to sea. The values used in

the surface water runoff equation are given in Table C-3.

Appendix Table C-4 gives threshold values of the equations.